Objective:To explore the effects of electroacupuncture pretreatment on mitochondrial energy metabolism in the rats with myocardial ischemia reperfusion injury(MIRI).Methods:A total of 60 SPF Wistar rats were randomly divided into a sham-operation group(sham group),a myocardial ischemia reperfusion injury group(MIRI group)and an electroacupuncture pretreatment group(EA group),20 rats in each one.The rats in the sham group and the MIRI group were binded for 7 days,once a day,20 min each time.On the 8th day,the sample was collected after the heart exposed for 50 min in thoractomy in the sham group and the sample was collected after ischemia for 20 min and reperfusion for 30 min in thoractomy in the MIRI group.In the EA group,the pretreatment intervention with electroacupuncture was applied at"Neiguan(内关PC6)","Guanyuan(关元CV4)"and"Zusanli(足三里ST36)"in the rats for 7 days,once a day,20 min each time.On the 8th day,after ischemia for 20 min and reperfusion for 30 min in thoractomy,the sample was collected in the EA group.The changes in STⅡsegment of electroacardiogram(ECG)were observed and measured.Using enzymelinked immunosorbent assay(ELISA),the concentrations of cardiac troponin T(cTnT)and cardiac troponin I(cTnl)were detected.Using nitro blue tetrazolium chloride monohydrate(NBT)staining,the myocardial infarction weight percentage was measured.Using ELISA,the concentrations of mitochondrial adenosine monophosphate(AMP),adenosine diphosphate(ADP)and adenosine triphosphate(ATP)were detected.Results:(1)STⅡchanges:in 20 min of ligation,compared with the sham group,the STⅡsegment of electrocardiograph(ECG)was elevated significantly in the MIRI group and EA group(both P<0.01),but the elevation range in the EA group was lower than that of the MIRI group(P<0.01).After reperfusion for30 min,the STⅡsegment was fallen by over 50%in the MIRI group and the EA group.Simultaneously,the STⅡsegment in the EA group was lower than that of the MIRI group(P<0.01).(2)Regarding myocardial infarction weight percentag